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    <meta charset="UTF-8">
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    <title>嵌套列表</title>
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    <ul>
        <li>
            辽宁省
            <ul>
                <li>沈阳</li>
                <li>大连</li>
                <li>丹东</li>
            </ul>
        </li>
        <li>山东省
            <ul>
                <li>济南</li>
                <li>青岛</li>
                <li>烟台</li>
            </ul>
        </li>
    </ul>
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